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PowerMaxOS monitors media defects by both examining the result of each data transfer and proactively scanning the entire drive during idle time. If a block is determined to be bad, the director:
The director maps around any bad block(s) detected, thereby avoiding defects in the media. The director also keeps track of each bad block detected. If the number of bad blocks exceeds a predefined threshold, the primary MMCS invokes a sparing operation to replace the defective drive and then automatically alerts Customer Support to arrange for corrective action.